When they were launched in 1977, the two Voyager spacecraft each carried with them a 12-inch gold-plated copper record containing multimedia pertaining to life on Earth, the idea being that if an extraterrestrial ran across one of these records millions of years from now, they could play it an learn something about our planet. This site has a listing of some of the music, images, and sounds contained on the records. Here are two of the images included…the first is a rudimentary mathematics primer and the second is a family portrait:
I wonder when we’ll see these records again. I mean, it seems more plausible that Elon Musk’s grandson will mount an expedition to retrieve a Voyager probe in 2077 than some alien running across the thing.